First of all, "environmentalists are against destruction of nature, including traditional methods" is an absurd argument. Environmentalists have to eat after all, and they would prefer to eat organically grown food. That is farmed. Obviously.
Also, it's important to realize that the AFA is the not the entire Farmer's Alliance, just like the NLH aren't the entirety of the Gaians. And the Gaians certainly aren't the entirety of the Green Front.